I was flying in the cross the Pacific yesterday on Vatsim. I had a problem with airspeed. I had autopilot set to 36000 feet, climb rate was set a 2000fpm, I had speed set to .70 mach, and clb set for power. I had fuel at about 50% in each tank. I have discovered that fuel weight greatly affects the overall ability to handle the climb out? Anyway, during climb my airspeed slowed to 160 knots and I eventually stalled and crashed. I tried to reduce the climb rate to 500 fpm, but it was too late. I was wondering if anyone might give me an insite to what I did wrong. Gear was up, flaps were retracted,speed brakes were off.ThanksMark TCyber Airlines

Don't use a V/S climb. It isn't used in real life in that situation as it does not offer speed (stall) protection. Climb in VNAV or LVL CHG instead. It will maintain an airspeed and achieve the best climb rate possible. 0.70 mach is fairly slow too. I think about 0.80 is more typical and is generally about what VNAV will use.Lee Hetherington (KBED)http://vatsim.pilotmedia.fi/statusindicato...tor=OD1&a=a.jpg

Can I use the other autopilot selections if I am not flying from the FMC? ThanksMark TCyber Air

MarkYou can use the FL CHG even if the FMC isn't properly setup. VNAV needs infomration from the FMC though.Hope it helps

I will try it tonight. thanks for the help!Mark TCyber Airlines

Mark,Others have answered your problem from an AFCS perspective butI noticed a few things in your post that you could do for added realism:1. Mach 0.8 is about where you want to keep your speed (as others have said, 0.70 is way too low -- 0.78 equates to LRC and above M0.82 the drag rise and therefore fuel consumption become problematic) and in fact during an oceanic clearance the mach number to maintain is part of that clearance. You must maintain that mach number even during step climbs and/or descents.2. Most of the Pacific is RVSM airspace and as such, it is recommended that you limit your V/S to a max of 1000 fpm for the last 1000 ft of climb. In any event, your climb rate would likely not exceed that value if you are climbing at cruise mach at a weight appropriate for the altitude.3. Use the FMS. I don't know how you could do a Pacific oceanic flight without it (since you can't navigiate directly from the INS in PIC 767). Cheers,Kevin in CYOW

Hi all,regarding climb profiles I have one question.I have noticed that when climbing in VNAV or FL-CHG mode passing FL280-290, the plane starts to pitch up and down continuosly following the FD bars to mantain the desired VNAV profile or the speed if in FL-CHG. All this starts at as I said around FL290. I set the ZFW correctly. Load fuel using a fuel calculator and always cruise at my OPT cruise altitude. For the climb I usually use mach0.80. Does anyone know why it does this? It's annoying seeing the V/S varying continuosly from 1000 to 1500-2000 FPM and back down!!At that point I manually select V/S and keep climbing at about 1000-1200 FPM.Any help or advice would be greatly appreciated, thanks.Regards,Bjorn